50 years of different landscape management influencing retention of metals in soils

The geochemical position of metals bound to soils in an area with 50 years of different landscape management practices (land use) during its unique historical development has been studied in this work. The three following localities were chosen for study: (i) afforested area, (ii) wetlands and (iii) pasture. Small changes in the soil physico-chemical properties have been detected between the studied catchments, however, significant differences in the geochemical position of metals were found in the upper soil horizons. Metals, e.g., Cr, Co, Ni, Cu, Zn, Pb and Tl are present mainly in non-residual forms in the forest organic soil horizons while in the pasture soils the predominant metal form is residual. It was demonstrated that soil organic matter (SOM) is responsible for metal retention in soils. Pasture soils with a lower amount of solid SOM are not able to retain the metals efficiently in the upper soil horizons. Therefore, these soils are much more vulnerable to possible anthropogenic contamination. The different landscape management types/practices did not influence the metal forms in deeper soil horizons because the metal distribution in the mineral soil horizon did not differ within the studied localities.

► > 50 years of different landscape management changed the retention of metals in soils.
► > The greatest contrast was found between forest and pasture localities.
► > Forest organic soil horizons retain the metals, e.g., Cr, Co, Ni, Cu, Zn, Tl and Pb.
► > Dry and poorer soils are not able to a great extent retain the metals.
► > Vulnerable soil system to anthropogenic contamination with metals are pasture soils.